Parts catchers or parts accumulators collect parts from production lines. Typically the parts are finished parts produced by feeding raw material, such as material in bar form, to a lathe. The lathe machines the raw material, shaping and cutting off a complete, or near complete part, which is then stored in the parts catcher. Often the parts catcher is simply a bucket on some type of movable arm that can extend at the proper time via the machine control so as to catch the work piece to be stored. After receiving the part from the lathe, the parts catcher retracts and deposits the work piece through an opening in the machine guarding either into a collection box on the front of the machine, or onto a straight conveyor, typically 3-4 feet in length. Then the machine can continue making the next piece.
Some parts catchers have very limited storage space, and hence they provide only a short amount of unmanned runtime, and/or they present a strong possibility of damaging the finished parts as they bang together. Such limitations presented by the parts catcher undermine one of the significant advantages of bar feeding—extended periods of unmanned run time.
Parts accumulators can be large and the space they occupy can interfere with efficiency.